Each year countless syringes are used throughout the world by the healthcare industry for the administration of liquid medications to humans and animals with hypodermic needles or infusion catheters, as well as for delivery of oral and topical medications. Some medications provided by pharmaceutical manufacturers are prepared, stored, and shipped as powders, crystals, or some other solid form due to the lack of stability in solution. These medications are then reconstituted with liquid, such as water or some other suitable liquid solvent. For one or several administrations of a medication, the manual filling of the syringes with reconstituted liquid medication is a small chore. However, larger health care institutions often administer medications in syringes to hundreds of patients per day, thus requiring the rather large chore of filling hundreds of syringes with medications and labeling each filled syringe to show the contents, strength, and fill dates, usually under the direction of a qualified pharmacist. Healthcare providers have found that preparing (e.g. filling and labeling) the quantities of syringes needed has many efficiencies and other advantages when it is done in batches.
In the later regard, batch preparation may be particularly preferred for syringes carrying medications that are not stable in liquid form and are therefore frozen after preparation to maintain acceptable stability. Further, the task of maintaining sterility in the transfer of liquid from containers provided by pharmaceutical manufacturers to pre-sterilized syringes may be enhanced by batch completion in controlled environments. Also, safety and overall reliability may improve when syringes are prepared in batches by pharmacy personnel or others who are dedicated to and well-trained for the task.
Currently, syringe preparation typically entails a number of separate operations with individual syringe handling. For example, systems used today fill syringes with dispensing pumps that are capable of delivering exact quantities of fluids but that require individual handling of each syringe. Peristaltic pumps that can be accurately calibrated, such as that described in U.S. Pat. No. 5,024,347, are often used. In such arrangements, the syringe caps are packaged so that sterility can be maintained in the capping procedure. The caps are located in trays where each cap is positioned so that the person doing the filling can manually place the tip of the syringe into the cap without touching or holding the cap. Labeling of the syringes has been done using a label dispenser similar to those used for applying pricing labels to grocery or other similar products.
With smaller syringes there are sometimes problems with getting sufficient label information on the syringe without covering over the syringe graduations or blocking the view of the medication. To overcome this, the labels are often applied by hand with the label wrapped around the syringe with most of the label extending from the syringe to form a flag.
Silicone lubricants are used in syringe manufacturing to provide lubrication for lowering the frictional force in movement of the syringe plunger. These silicone lubricants have a characteristic of migrating over all surfaces. Often, this migration causes difficulties in getting pressure sensitive labels to stay in place. This has caused users to use a clear plastic tape to wrap completely around the syringe and the label.
Efforts to automate hospital or clinic-based syringe preparation have been made, but most systems have automated only portions of the process and still require human intervention during critical stages of the process. In one such system, caps are pre-positioned in a cartridge holder. The syringes are also provided in a cartridge where each syringe is oriented. The machine to perform the filling and capping function requires an operator to load the cartridges of caps and syringes. The filling is done with a calibrated peristaltic pump. The machine fills each syringe and places a cap on the tip of the syringe. The labeling is done separately by a labeling machine that is commercially available.
As may be appreciated, the tips of syringes may be provided with a male luer fitting. In this regard, male luer fittings are utilized in a wide variety of medical liquid transfusion, infusion and injection applications. By way of example, ISO standards 594-1 and 594-2 (i.e. as published by the International Organization for Standardization) set forth specifications for conventional male luer fittings.
In one application, male luer fittings are provided on disposable syringes for selectively receiving a hub from which a needle projects. The hub is sized to slidably and sealably receive a complimentary nozzle of the male luer fitting. Typically, to enhance the reliability of interconnection, the male luer fitting includes an annular collar that is disposed about the nozzle and internally threaded for rotatably engaging outer threads provided on the hub of the needle.
In another primary use, male luer fittings are utilized in combination with complimentary female luer fittings to provide for the ready interconnection/disconnection of medical liquid tubing lines and/or outlet ports of medical liquid sources. In such applications, the female luer fitting is sized to slidably and sealably receive a complementary nozzle of the male luer fitting. By way of example, the use of connectable male luer and female luer fittings facilitates the fluid interconnection/disconnection of patients to medical liquid sources during extended therapy and otherwise allows for the replacement of medical liquid sources and/or associated tubing line sets in the course of extended therapy. Typically, to enhance the reliability of interconnections, the male luer fitting includes an annular collar that surrounds the nozzle and is internally threaded to rotatably engage outer threads disposed on the female luer fitting.
In connection with the noted uses of male luer fittings, it is generally desirable to provide a cap on a male luer fitting prior to and/or in-between the intended interconnection(s). Such caps are generally utilized to maintain a desired degree of sterility at the nozzle of the male luer fitting. Further, when male luer fittings are used in connection with syringes filled with a medical liquid (e.g. pre-filled with a liquid medication or flush solution), caps may also function to prevent leakage of the contained medical liquid. Similarly, caps serve to preclude the passage of liquid through connectors employed in connection with medical liquid tubing lines and/or outlet ports of medical liquid sources.
Collared male luer fittings of the type noted above are often referred to as “luer lock fittings”. When such luer lock fittings are utilized, caps employed therewith may be provided with interfacing annular members having external threads that are complimentary with the internally threaded collars of the male luer fittings. Such caps must necessarily be rotatably advanced/retracted relative to the male luer fittings in order to achieve interconnection/disconnection with the threaded collars. Further, in that regard, in automated systems for capping/uncapping collared male luer fittings (e.g. in conjunction with the automated assembly and/or filling of a disposable syringe), the utilization of caps having threaded annular members may increase equipment complexity since each cap and/or interfacing male luer fitting must be supportably disposed for both automated linear and rotational movement.